Please ensure JavaScript is enabled for purposes of website accessibility Frequently Asked Questions About Urea Cycle Disorders | For HCPs

You Are Leaving UCDinMind.com

You are about to go to an external website operated by an independent third party. Your activities at the external website will be managed by their policies and practices. By clicking “Continue,” you will go to the external website.

Continue

Frequently Asked Questions About Ammonia

Below are answers to common questions about high ammonia levels.

Open all

  • What is a normal ammonia level?

    Normal ammonia levels vary according to age. Gestational and postnatal ages may affect ammonia levels in newborns.1

    Patient Age Normal Ammonia Level Range
    Healthy term infants 45 ± 9 µmol/L; 80-90 µmol/L is considered to be the upper limit of normal
    Preterm infants 71 ± 26 µmol/L, decreasing to term levels in approximately 7 days
    Children older than 1 month of age Less than 50 µmol/L
    Adults Less than 30 µmol/L

    *Normal ranges for blood free ammonia concentration vary from laboratory to laboratory.

  • What are the signs of high ammonia levels?

    High ammonia levels commonly manifest as nonspecific symptoms or neurological effects.1,2

  • Can high ammonia levels cause central nervous system damage?

    Elevated levels of ammonia may cause neurological signs and symptoms that may vary depending on the causative disorder. Left untreated, high ammonia levels may lead to potentially life-threatening complications including cerebral edema, brain herniation, raised intracranial pressure, and coma.1,3

  • Can high ammonia levels cause hallucinations?

    Patients may experience psychiatric symptoms, including hallucinations, mood swings, and personality changes, due to hyperammonemia.2,4,5

  • What diet is best for high ammonia levels?

    Depending on the underlying cause of hyperammonemia, protein-restriction may be appropriate to help control elevated ammonia levels.

  • What causes high ammonia levels?

    High ammonia levels may be caused by any number of disorders, including1,6

    • Cirrhosis or hepatitis
    • Certain genetic disorders, including urea cycle disorders
    • Reye’s syndrome

    This is not an exhaustive list of causes of hyperammonemia. If an underlying disorder is suspected, a diagnosis should be made based on relevant clinical information in conjunction with ammonia level test results.

  • How to test for high ammonia levels?

    Measuring ammonia levels requires a blood draw for laboratory testing. However, ammonia level testing may be challenging. Learn about the correct procedures for ammonia level testing.7,8

  • References

    1. Ali R, Nagalli S. Hyperammonemia. In: StatPearls. StatPearls Publishing; 2023. Accessed March 13, 2023. https://www.ncbi.nlm.nih.gov/books/NBK557504/ 2. Häberle J, Burlina A, Chakrapani A, et al. Suggested guidelines for the diagnosis and management of urea cycle disorders: first revision. J Inherit Metab Dis. 2019;42(6):1192-1230. 3. Ah Mew N, Simpson KL, Gropman AL, et al. Urea cycle disorders overview. In: Adam MP, Mirzaa GM, Pagon RA, et al, eds. GeneReviews®. University of Washington, Seattle; 2017. Accessed March 13, 2023. http://www.ncbi.nlm.nih.gov/books/NBK1217/. 22. 4. Gardeitchik T, Humphrey M, Nation J, Boneh A. Early clinical manifestations and eating patterns in patients with urea cycle disorders. J Pediatr. 2012;161(2):328-332. 5. Krivitzky L, Babikian T, Lee HS, Thomas NH, Burk-Paull KL, Batshaw ML. Intellectual, adaptive, and behavioral functioning in children with urea cycle disorders. Pediatr Res. 2009;66(1):96-101. 6. National Institutes of Health. Ammonia Levels. National Institutes of Health; 2023. https://medlineplus.gov/lab-tests/ammonia-levels/ 7. Barsotti RJ. J Pediatr. 2001;138(suppl 1):S11-S20. Gardeitchik T, Humphrey M, Nation J, Boneh A. Early clinical manifestations and eating patterns in patients with urea cycle disorders. J Pediatr. 2012;161(2):328-332. 8. Häberle J, Boddaert N, Burlina A, et al. Suggested guidelines for the diagnosis and management of urea cycle disorders. Orphanet J Rare Dis. 2012;7:32.